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Majeed A, Lehmann P, Kirby L, Knight R, Coleman M. Extent of misclassification of death from Creutzfeldt-Jakob disease in England 1979-96: retrospective examination of clinical records. BMJ (CLINICAL RESEARCH ED.) 2000; 320:145-7. [PMID: 10634732 PMCID: PMC27259 DOI: 10.1136/bmj.320.7228.145] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To investigate the extent to which deaths from Creutzfeldt-Jakob disease were misclassified during 1979-96. DESIGN Structured review of clinical records based on predetermined criteria to determine whether death could have been due to sporadic or variant Creutzfeldt-Jakob disease. SETTING 100 health authorities and 275 NHS trusts in England. SUBJECTS 1485 people who died aged 15-44 years from selected neurological disorders in England during 1979-96. MAIN OUTCOME MEASURE Cause of death. RESULTS The clinical records of 705 (48%) subjects were successfully traced. Tracing of clinical records was highest in subjects who died during 1990-6. There was sufficient information in the records of 640 (91%) of the 705 subjects to exclude Creutzfeldt-Jakob disease as a cause of death. In 61 (9%) subjects, there was insufficient information to reach any conclusion about the validity of the cause of death recorded on the death certificate. The clinical records of four subjects were examined further by the National Creutzfeldt-Jakob Disease Surveillance Unit; none was thought to have died from Creutzfeldt-Jakob disease. CONCLUSIONS No new cases of sporadic or variant Creutzfeldt-Jakob disease were detected in a sample of deaths most likely to have included misclassified cases. This suggests that the surveillance system is unlikely to have missed a significant number of cases among people aged 15-44 years. Hence, any rapid increase in the number of cases of variant Creutzfeldt-Jakob disease in this age group is likely to be real not artefactual.
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Kirby L, Abbas J, Brophy C. Recanalization of an occluded popliteal artery following posterior knee dislocation. Ann Vasc Surg 1999; 13:622-4. [PMID: 10541618 DOI: 10.1007/s100169900310] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Posterior knee dislocation results in popliteal artery injury in up to one-third of cases. Prompt recognition and treatment of arterial injury is essential for limb salvage. We report a case of complete occlusion of the popliteal artery following posterior knee dislocation treated with saphenous vein bypass without exclusion of the injured arterial segment. Follow-up duplex scanning demonstrated a patent vein graft and a patent ipsilateral popliteal artery. This report suggests that, in some instances, a traumatically occluded popliteal artery may recanalize, and that revascularization with a bypass graft may be the preferred method of repair, particularly in young patients.
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MacGregor I, Hope J, Barnard G, Kirby L, Drummond O, Pepper D, Hornsey V, Barclay R, Bessos H, Turner M, Prowse C. Application of a time-resolved fluoroimmunoassay for the analysis of normal prion protein in human blood and its components. Vox Sang 1999; 77:88-96. [PMID: 10516553 DOI: 10.1159/000031082] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND AND OBJECTIVES To quantify the cellular isoform of prion protein (PrP(c)) in human blood using a new time-resolved dissociation-enhanced fluoroimmunoassay (DELFIA). MATERIALS AND METHODS The DELFIA was optimised for human blood samples and applied to isolated cell and plasma fractions from blood donations. The physicochemical properties of PrP(c) were analysed. RESULTS 26. 5% of blood PrP(c) was associated with the platelet fraction, 0.8% with polymorphonuclear leucocytes, 2.4% with mononuclear leucocytes, 1.8% with red cells and 68.5% with plasma (mean values from 4 processed donations). CONCLUSION The majority of blood PrP(c) is found in the platelet and plasma compartments.
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Prowse CV, Hornsey VS, Drummond O, MacGregor IR, Pepper DS, Barclay GR, Bethel H, Walker B, Barnard G, Kirby L, Hope J. Preliminary assessment of whole-blood, red-cell and platelet- leucodepleting filters for possible induction of prion release by leucocyte fragmentation during room temperature processing. Br J Haematol 1999; 106:240-7. [PMID: 10444194 DOI: 10.1046/j.1365-2141.1999.01530.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Universal leucodepletion is being introduced in the U.K. to reduce a theoretical risk of Creutzfeldt-Jakob disease (CJD) transmission. If CJD infectivity is associated with leucocytes, any cell fragmentation associated with filtration could reduce the potential benefit. Four types each of whole blood, red cell and platelet leucodepletion filters were assessed after holding of blood units for at least 4 h at 22 degrees C. In all cases the mean residual leucocyte content was <1 000 000 per unit, with only two individual filtered whole blood units having a leucocyte content exceeding this. Evidence of leucocyte fragmentation during filtration was sought but not found by assay of soluble elastase, beta-thromboglobulin and normal prion protein, as well as by isotopic labelling of leucocyte external membrane. These preliminary studies indicate that it was possible to prepare leucodepleted blood components by filtration at room temperature, and that this appeared not to be associated with overt cell fragmentation. Definitive demonstration that fragmentation does not occur requires the development of improved general (non-specific) assays for cell membrane fragments.
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Levy EI, Scarrow AM, Firlik AD, Kanal E, Rubin G, Kirby L, Yonas H. Development of obstructive hydrocephalus with lumboperitoneal shunting following subarachnoid hemorrhage. Clin Neurol Neurosurg 1999; 101:79-85. [PMID: 10467901 DOI: 10.1016/s0303-8467(99)00010-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Hydrocephalus is a frequent complication of subarachnoid hemorrhage (SAH). The optimum method of treating hydrocephalus in this setting has not been determined. We review our experience with patients developing communicating hydrocephalus secondary to SAH and subsequently treated with lumboperitoneal (LP) shunts. Following hospitalization for the treatment of SAH, patients who developed clinical symptoms and radiologic signs of hydrocephalus were treated with (ventriculoperitoneal) VP or LP shunting. Eighteen patients received an LP shunt, of which seven (28%) developed a non-communicating or obstructive hydrocephalus. These seven patients underwent replacement with a VP shunt and have not had further complications. In the setting of post-SAH communicating hydrocephalus, obstructive hydrocephalus may develop after LP shunt placement. Patients who develop this complication and have their LP shunts converted to VP shunts have a favorable prognosis.
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Kling KM, Kirby L, Kwan KY, Kim F, McFadden DW. Interleukin-10 inhibits inducible nitric oxide synthase in an animal model of necrotizing enterocolitis. INTERNATIONAL JOURNAL OF SURGICAL INVESTIGATION 1999; 1:337-42. [PMID: 12774458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
BACKGROUND Nitric oxide (NO) and its role in surgical inflammation are well documented; demonstrating the role of NO in necrotizing enterocolitis (NEC) and ways in which it may be suppressed may provide avenues for immune modulation in the treatment of NEC. AIMS We sought to demonstrate an increase in inducible nitric oxide synthase (iNOS) mRNA and nitric oxide in an experimental model of necrotizing enterocolitis. In addition, we hypothesized that interleukin-10 (IL-10) would attenuate this response. METHODS Newborn rats were treated with 25 microliters intraperitoneal IL-10 or vehicle prior to laparotomy, 1 h superior mesenteric artery (SMA) occlusion, 50 micrograms/kg intraluminal platelet activating factor administration, and SMA reperfusion. iNOS mRNA and nitric oxide levels were measured in the liver, small bowel, and serum and compared using Student's t-test. RESULTS Small bowel iNOS mRNA increased after NEC induction from 0.058 +/- 0.02 to 0.144 +/- 0.05 relative intensity units (RIU) at 2 h (p < 0.01) and from 0 to 0.09 +/- 0.02 RIU at 6 h (p < 0.03). Liver mRNA increased from 0.026 +/- 0.002 to 0.485 +/- 0.09 RIU (p < 0.002) and from 0 to 0.069 +/- 0.02 RIU (p < 0.0001) at 2 and 6 h, respectively. Serum nitric oxide increased in NEC induced animals at 2 h from 28.04 +/- 10.5 to 45.18 +/- 6.8 microM (p < 0.001). IL-10 suppressed iNOS mRNA and nitric oxide expression at 2 h in small bowel, liver, and serum by 60%, 89%, and 11%, respectively. CONCLUSIONS IL-10 decreases iNOS mRNA response in experimental NEC. This down-regulation may be an avenue for anti-inflammatory intervention in NEC.
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McKay IA, Kirby L, Volyanik EV, Kumar V, Wong PW, Bustin SA. An enzyme-linked immunosorbent assay for the detection of agents which interfere with the DNA binding activities of transcription factors--exemplified by NF-IL6. Anal Biochem 1998; 265:28-34. [PMID: 9866704 DOI: 10.1006/abio.1998.2869] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Binding of transcription factors to DNA is usually detected by the electrophoretic mobility shift assay also known as gel-shift or band-shift assay. Recently the use of biosensors has allowed factor/DNA interactions to be followed in real time. However, neither of these approaches lends itself easily to high-throughput screening of agents which might interfere with this process. We have therefore developed a 96-well plate-based enzyme-linked immunosorbent assay for this purpose. Biotinylated oligonucleotides bound to streptavidin-coated plates are used to capture recombinant transcription factor proteins which can then be detected using specific antibodies which in turn are recognised by peroxidase-conjugated antisera. The peroxidase catalyzes conversion of a colorless substrate to a colored product which can be quantified by optical densitometry on a plate reader. Agents which interfere with the binding of the transcription factor to DNA reduce the optical density in the well. Using the NF-IL6 transcription factor we show that the assay can detect reductions to 86% at significant levels. The assay may be readily adapted for robotic manipulation, making it ideal for high-throughput screening.
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Matsuura JH, Rosenthal D, Clark M, Shuler FW, Kirby L, Shotwell M, Purvis J, Pallos LL. Transposed basilic vein versus polytetrafluorethylene for brachial-axillary arteriovenous fistulas. Am J Surg 1998; 176:219-21. [PMID: 9737637 DOI: 10.1016/s0002-9610(98)00122-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Both transposed basilic vein (BV) and polytetrafluorethylene (PTFE) upper arm arteriovenous fistulas (AVF) are common angioaccess operations. To evaluate the patency and complication rates after AVF, a concurrent series of patients was reviewed. METHODS Ninety-eight patients underwent brachial artery to axillary vein AVF: 30 BV and 68 PTFE. The PTFE grafts were performed in the standard fashion, whereas the basilic veins were translocated subcutaneously to the brachial artery. RESULTS Risk factors were similar between the two groups. Basilic vein AVF had better patency at 24 months (70% BV versus 46% PTFE, P = 0.023). The dialysis access complications were higher in the BV group (20%) versus PTFE (5%), but the PTFE group had a higher infection rate (10%) than BV (0%). CONCLUSIONS The primary and secondary patency rates were superior in the BV AVFs. The BV AVF preserves the venous outflow tract after AVF thrombosis for a future PTFE AVF operation.
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Majeed A, Lehmann P, Kirby L, Coleman MP. Mortality from dementias and neurodegenerative disorders in people aged 15-64 in England and Wales in 1979-96. BMJ (CLINICAL RESEARCH ED.) 1998; 317:320-1. [PMID: 9685278 PMCID: PMC28625 DOI: 10.1136/bmj.317.7154.320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Kirby L, Lehmann P, Majeed A. Dementia in people aged 65 years and older: a growing problem? POPULATION TRENDS 1998:23-8. [PMID: 9679268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This study examines trends in death rates from dementias and neurodegenerative disorders in people aged 65 and over in England and Wales between 1979 and 1996. In total, there were 171,590 deaths from dementias and neurodegenerative disorders, with the number of deaths per year increasing from 3,021 in 1979 to 10,415 in 1996. Age-standardised death rates for all diagnoses combined increased from 39 to 96 per 100,000 for men and from 45 to 101 for women between 1979 and 1996. The most dramatic increase was seen in death rates from Alzheimer's disease which increased from less than 1 per 100,000 in 1979 to 19 for men and 21 for women in 1996.
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Machesney M, Tidman N, Waseem A, Kirby L, Leigh I. Activated keratinocytes in the epidermis of hypertrophic scars. THE AMERICAN JOURNAL OF PATHOLOGY 1998; 152:1133-41. [PMID: 9588880 PMCID: PMC1858601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The etiology of hypertrophic scarring, a pathological end point of wound healing, is unknown. The scars most commonly occur when epithelialization has been delayed during, for example, the healing of deep dermal burn wounds. Hypertrophic scars are conventionally described as a dermal pathology in which the epidermis has only a passive role. In this study, the expression of keratin intermediate filament proteins and filaggrin has been investigated in the epidermis of hypertrophic scars and site-matched controls from the same patients. Hypertrophic scar epidermis was found to express the hyperproliferative keratins K6 and K16 in interfollicular epidermis in association with K17 and precocious expression of filaggrin. K16 mRNA was localized by in situ hybridization using a highly specific cRNA probe. In contrast to the immunohistochemical location of K16 protein, the K16 mRNA was found to be expressed in the basal cell layer of normal skin. In hypertrophic scars the mRNA distribution corroborated the abnormal K16 protein distribution. These results suggest the keratinocytes in hypertrophic scar epidermis have entered an alternative differentiation pathway and are expressing an activated phenotype. Activated keratinocytes are a feature of the early stages of wound healing producing growth factors that influence fibroblasts, endothelial cells, and the inflammatory response. We propose that cellular mechanisms in the pathogenesis of hypertrophic scarring are more complex than isolated dermal phenomena. The persistence of activated keratinocytes in hypertrophic scar epidermis implicates abnormal epidermal-mesenchymal interactions.
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Levy EI, Scarrow AM, Kanal E, Rubin G, Yonas H, Kirby L. Reversible ischemia determined by xenon-enhanced CT after 90 minutes of complete basilar artery occlusion. AJNR Am J Neuroradiol 1998; 19:1943-6. [PMID: 9874552 PMCID: PMC8337725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Intraarterial thrombolytic therapy decreases mortality in the treatment of acute basilar artery occlusion. An acute decrease in cerebral blood flow (CBF) (<12 mL/100 g per minute) has been reported to invariably result in infarction. We report a case of acute basilar artery occlusion, recanalized within 90 minutes, with reversal of CBF of less than 6 mL/100 g per minute. After reperfusion, areas with persistent CBF of 6 mL/100 g per minute resulted in infarctions on subsequent CT studies. Parenchymal viability is possible after 90 minutes of posterior CBF of 6 mL/100 g per minute.
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Lee L, Goor E, Kennedy C, Walters S, Kirby L. Non-acute casemix in the Illawarra. JOURNAL OF QUALITY IN CLINICAL PRACTICE 1994; 14:23-30. [PMID: 8199755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
There are problems associated with the use of acute care diagnosis-related groups for prospective payment for rehabilitation medicine services. As a preliminary effort to assist in the development of the National Non-Acute Inpatient Casemix Project, a modified costing study was done in the rehabilitation and geriatrics ward of the Illawarra Regional Hospital; its aim was to assess the validity of the functional independence measure (FIM) and the resource utilization group (RUG) system as predictors of staff time involvement in inpatient rehabilitation services. Data collected on 51 patients over 3 months showed that in a standard Australian rehabilitation unit the costs of staff involvement varied depending on the type of functional impairment and severity of carer burden. The FIM alone was not predictive of rehabilitation costs and the RUG 2 instrument was not comprehensively predictive of cost. The RUG 3 instrument developed in the USA did not allocated weightings appropriate to Australian costs. If, however, functional impairment groups were combined with one of these measures of carer burden, then costs did fall into categories reflective of staff time involvement. An Australian system which incorporates an instrument measuring functional capacity may be useful for resource allocation in rehabilitation care.
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Smith CJ, Owen C, Kirby L. Activation of a cryptic streptomycin-resistance gene in the Bacteroides erm transposon, Tn4551. Mol Microbiol 1992; 6:2287-97. [PMID: 1328814 DOI: 10.1111/j.1365-2958.1992.tb01404.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Bacteroides compound transposons encoding erm resistance are highly homologous but previous studies have shown some divergence of Tn4551. Results presented here describe a novel Tn4551 streptomycin-resistance gene, aadS, that was phenotypically silent in wild-type Bacteroides. However, aadS expression could be activated by a trans-acting chromosomal mutation. The aadS-encoded peptide displayed significant homology to Gram-positive streptomycin-dependent adenyltransferases, and enzymatic analysis confirmed the production of this activity. Examination of the nucleotide sequence showed that 200 bp upstream of aadS, the DNA base composition changed abruptly from 31% G+C to 48% G+C. These two regions were demarcated by a DNA sequence with homology to the recombination hot spots reported for Tn21 and the Bacteroides ermFU gene and to sequences at the ends of the chromosomal Bacteroides conjugal element, XBU4422.
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Hahn P, Taller M, Srubiski L, Kirby L. Regulation of ketone formation and phosphoenolpyruvate carboxykinase activity in the small intestinal mucosa of infant rats. BIOLOGY OF THE NEONATE 1991; 60:1-6. [PMID: 1912094 DOI: 10.1159/000243382] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We studied the effect of different hormones added in vivo or in vitro on ketogenesis and phosphoenolpyruvate carboxykinase (PEPCK) activity in the small intestinal mucosa of suckling rats. Injection of insulin or dexamethasone in vivo or of an antiglucagon antiserum decreased the rate of ketone formation in the mucosa whereas injection of anti-insulin antiserum led to increased mucosal ketogenesis. PEPCK activity in the mucosa was decreased by the antiglucagon serum but was not affected by insulin or anti-insulin serum injections. Both liver and brown fat PEPCK responded as expected with the activity being elevated by anti-insulin serum and depressed by both insulin and antiglucagon serum. In the in vitro experiments, no effect of any of the agents on PEPCK was found. Ketone formation was suppressed in vitro by insulin or dexamethasone addition to the medium.
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Hayden MR, Vergani C, Humphries SE, Kirby L, Shukin R, McLeod R. The genetics and molecular biology of apolipoprotein CII. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1986; 201:241-51. [PMID: 3541518 DOI: 10.1007/978-1-4684-1262-8_21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Wood S, Daya M, Allanson JE, Kirby L, Coupland R, Gray GR. Partial deletion of the beta-globin gene: a common beta-thalassaemia allele in Asian Indians. CANADIAN JOURNAL OF GENETICS AND CYTOLOGY. JOURNAL CANADIEN DE GENETIQUE ET DE CYTOLOGIE 1984; 26:296-301. [PMID: 6329492 DOI: 10.1139/g84-046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We have examined 11 families of Asian Indian origin, who are segregating beta-thalassaemia alleles, for coupled restriction enzyme site markers. A beta-thalassaemia deletion allele, which removes over 600 base pairs, is a common cause of thalassaemia in this population. This deletion can be conveniently detected in AvaII restriction enzyme digests. Consequently AvaII digests are particularly informative in this population because both the deletion and a coupled restriction site polymorphism may be simultaneously observed.
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Applegarth DA, Kirby L. Annotated bibliography: chorionic villus biopsy and diagnosis of inherited diseases using recombinant DNA analysis. PEDIATRIC PATHOLOGY 1984; 2:501-2. [PMID: 6399106 DOI: 10.3109/15513818409025897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Blankinship RT, Kirby L, Montague C. Total capital equipment programs: a new direction for group purchasing. HOSPITAL MATERIEL MANAGEMENT QUARTERLY 1982; 3:7-11. [PMID: 10254139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
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Hahn P, Seccombe D, Kirby L, Girard J, Assan R, Kervran A. Regulation of phosphoenolpyruvate carboxykinase and fatty acid synthetase in brown fat of suckling rats. Endocrinology 1978; 103:1417-24. [PMID: 744153 DOI: 10.1210/endo-103-4-1417] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Infant rats were injected with prednisolone (0.5-5 mg/100 g wt). This caused phosphoenolpyruvate carboxykinase (PEPCK) activity to rise in liver and to decrease in brown fat. Fatty acid synthetase (FAS) activity remained unchanged in liver but increased in brown fat. A single injection of prednisolone caused hepatic PEPCK activity to remain elevated for at least 7 days. Brown fat FAS also remained high for that period. However, brown fat PEPK activity returned to normal on the third day after the injection. A single injection of prednisolone or cortisone to 5-day-old rats caused a transient elevation of the blood level of insulin and a prolonged decrease in that of growth hormone. No effect on the level of glucagon was noted. Injections of insulin had effects similar to those of prednisolone, i.e. a rise in hepatic and a fall in brown fat PEPCK. Using antibodies prepared to hepatic PEPCK it was shown that the observed changes were due to changes in the rate of synthesis of the enzyme. Using actinomycin D indirect evidence was obtained that changes in FAS activity of brown fat were also due to changes in the synthetic rate.
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Kirby L, Hahn P. Changes in tyrosine transaminase and phosphoenolpyruvate kinase activities during short term incubation of fetal liver. Pediatr Res 1976; 10:243-5. [PMID: 5698 DOI: 10.1203/00006450-197604000-00009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Incubation of fetal rat liver homogenates at 37 degrees for 2-3 hr increased PEPK activity in the 100,000 X g supernatant 5-fold and TTA activity 10-fold. At the same time, activity in the 100,000 X g pellet decreaed and no change was observed in the whole homogenate. It is concluded that during incubation of fetal liver pieces or homogenates in vitro, a redistribution of enzymes occurs between cell particles and cell sap. It is suggested that release of enzyme into the cell sap may be the first stimulus for subsequent enzyme synthesis which occurs after birth.
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Dodek P, Kirby L, Frohlich J, Hahn P, Ho-Yuen B. High glucose concentration and phosphoenolpyruvate carboxykinase activity in human and rat fetal liver cultures. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 1975; 150:7-10. [PMID: 1237892 DOI: 10.3181/00379727-150-38962] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In cultures of human and rat fetal liver, phosphoenolpyruvate carboxykinase activity increases during the first 24 hr of culturing. This increase can be suppressed by adding cycloheximide to the culture medium or by adding a high glucose concentration. This, however, applies only to human fetal liver and to fetal liver from rats obtained just before term. In younger rat fetal liver, glucose, on the contrary, increases the activity of phosphoenolpyruvate carboxykinase. A high glucose concentration in the medium also leads to higher citrate cleavage enzyme activity and to lower alpha-glycerolphosphate dehydrogenase (cytoplasmic) activity in rat fetal liver cultures.
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Hahn P, Kirby L. Immediate and late effects of premature weaning and of feeding a high fat or high carbohydrate diet to weanling rats. J Nutr 1973; 103:690-6. [PMID: 4710080 DOI: 10.1093/jn/103.5.690] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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Kirby L, Hahn P. Enzyme activities during culturing of fetal rat liver. CANADIAN JOURNAL OF BIOCHEMISTRY 1973; 51:476-81. [PMID: 4144481 DOI: 10.1139/o73-056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Liver from fetal rats was cultured in a simple medium. In such cultures tyrosine transaminase (TTA) activity had increased after 20 min and reached twice the initial value within 2 h. Phosphoenolpyruvate earboxykinase (PEPCK) activity decreased during culturing. Incubation of microsomes from fresh fetal liver with dibutyryl cyclic AMP (DcAMP), oleic acid, or acetyl-CoA led to an increase in their TTA activity. It is suggested that the early rise in TTA during culturing is due to release of the enzyme from the microsomal fraction. In contrast to human fetal liver, oleic acid did not induce PEPCK in rat fetal liver cultures. In neither species was there an effect of DcAMP on the amount of fatty acids in the culture medium or on the activities of carnitine acetyl- and carnitine palmitoyltransferases.
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